By Jeffrey A. Lockwood & Alexandre V. Lachininsky
July-September 2008 / Vol. 9 No. 3
Discussion Questions
- What ecological arguments do the authors give for removing the gray bird grasshopper from Nihoa? What ecological arguments do they give for not removing it? Ultimately, they were unable to remove this insect because of technological limitations, but imagine that those limitations didn’t exist. How might you go about deciding between these two options?
- The decision to remove an exotic species is, in effect, a decision to restore a site to some previous “natural” state. The authors mention that this raises the question of what previous timeframe is the right one. What kinds of things might you consider when trying to answer that question for a particular site?
- What kinds of arguments other than ecological might you want to consider when thinking about whether or not to remove an exotic species?
- The authors state their belief that human subjectivity justifies the removal of exotic species, suggesting that an appeal to subjectivity runs counter to normal scientific practice. However, the use of subjective beliefs (“values”) is common in conservation biology; for example, conservation tries to prevent species from going extinct because extinction is “bad.” What other kinds of values are associated with conservation? Can you think of any other sciences where values are common?
- The authors finally concluded that removal of the grasshopper was justified. Why? Do you agree with their logic? Do you agree with their decision?
Websites for Further Information
- Nihoa Island: http://www.hawaiianatolls.org/about/nihoa.php
- Photos of the Gray Bird Grasshopper: http://bugguide.net/node/view/19507/tree
- Invasive and exotic species in the U.S.: http://www.invasive.org/
Invasive Species in the News
- New climate report foresees big changes (The New York Times, May 28, 2008)
- Tiny but hungry, moth may peril California crops (The New York Times, June 18, 2007)
- Exotic surprises (Honolulu Star-Bulletin, November 4, 2006)
Peer-reviewed Literature
- Latchininsky, A.V. 2008. Grasshopper outbreak challenges conservation status of a small Hawaiian Island. Journal of Insect Conservation 12: 343-357.
- Lockwood, J.A., and A.V. Latchininsky. 2008. Philosophical justifications for the extirpation of non-indigenous species: the case of the grasshopper Schistocerca nitens (Orthoptera) on the Island of Nihoa, Hawaii. Journal of Insect Conservation 12: 429-445.
- Bram, R.A., and J.E. George. 2000. Introduction of nonindigenous arthropod pests of animals. Journal of Medical Entomology 37: 1-8.
Key Concepts
- Invasive species
- Exotic species
- Conservation philosophy
- Island ecology
- Insect
- Eradication
